In the case of one such hand powered liquid atomizer with a pistol-like housing (see German Offenlegungsschrift No. 2 101 445), the flange is next to a part of the holding part which is somewhat conical in form and is force fitted into a matching, somewhat conical pocket in the handle part. The flange has an air inlet hole through it which communicates with the outside air. Between the lower end face of the flange and the top edge of the vessel neck there is an elastic ring-diaphragm whose ring-like part is gripped between the flange and the top edge of the vessel so as to form a seal. Next to this ring-like part there is a frusto-conical part having a hole through its middle. At the edge of this middle hole this frusto-conical part rests against a middle tube extending down from the flange, a flexible pipe being plugged into the tube and extending into the vessel. Normally the frusto-conical part of the ring-diaphragm rests against the tube so that when the atomizer is being shipped or is being used, liquid will be kept from running out of the vessel. On operating the pump of the atomizer, a vacuum will be produced in the flexible pipe and liquid will be aspirated out of the vessel so that, in turn, a vacuum will be produced in the vessel. This vacuum is then to be overcome by lifting the edge of the frusto-conical part of the ring-diaphragm away from the tube so that air may make its way into the vessel.
Quite in addition to the fact that the ring-diaphragm is a further, separate part of the atomizer which has to be manufactured and put in place separately and is likely to come off a liquid atomizer that is loose and not screwed on a vessel, for example while being shipped to the filling plant, it is very hard to ensure that the ring-diaphragm is made with such a quality of material and such a thickness that on the one hand the diaphragm will be seated air-tightly on the tube all the time that no air is to be let in, while, on the other hand, it is lifted clear of the tube when there is the least degree of vacuum in the vessel. Such lifting of the diaphragm is in fact only possible when the inner diameter of the frusto-conical part is elastically widened. The letting of air into the vessel to overcome a vacuum therein is more specially desired if there is a chance of the liquid diffusing out through the wall of the vessel. Most such vessels are made of synthetic resin. A vacuum will be produced by such diffusion and if the wall is thin, it will be partly collapsed and will take on a dented form if no air is let into it to overcome the least degree of vacuum.
A purpose of the invention is that of designing a hand powered liquid atomizer of the sort noted hereinbefore in such a way that the number of parts near and at the union nut is cut down, so that the manufacture and assembly of the parts will be cheaper and parts will be kept from coming off and being lost, while at the same time the equalization of pressure between the inside of the vessel and the air outside is made more perfect.